You need to be very careful when doing tug work with a young puppy. A puppies gums are sensitive and can be painful. Doing too much tug work can be damaging to a young pup. You can pull teeth out and if the dog is sensitive he will remember that painful experience for a long time. I would stop doing any bite work, even rag or tug work until all of his adult teeth are in. lay off for a good month or so. If you are new to bite work you may be doing more harm than good at this age.
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